An example of high frequency circuit module is an evaluation board for measurement of high frequency characteristics of signaling channels inclusive of cables and connectors. A known evaluation board as disclosed in Patent Literature 1 is mounted with a connector for connection with a cable and a coaxial connector for connection with a measuring instrument. The evaluation board has a wiring pattern and the like to establish electrical connection between the connectors.
Patent Literature 1: Japanese Unexamined Patent Publication No. 2007-165945
Among others, in evaluation boards supporting high-speed differential signaling such as ones compliant with DisplayPort (a standard for digital interfaces), the working frequencies are as high as several GHz or higher. Such evaluation boards are required to use a connector for cable connection and a wiring pattern that are designed with full consideration to impedance matching, minimization of skew (temporal delay between transmission lines), and reduction of crosstalk.